Screening means for clamshell bucket



Jan. 24, 1967 E. F. FREYEZR SCREENING MEANS FOR CL AMSHELL BUCKET 2 Sheets-Sheet 1 Filed Feb. 10, 1964 t 'rnesf F Freyer I N VENTOR.

Jan. 24, 1967 E. F. FREYER SCREENING MEANS FOR CLAMSHELL BUCKET Filed Feb. 10, 1964 Fig. 4 32 2 Sheets-Sheet F/ .5

Ernest f-T Freyer INVENTOR.

' of the sectional bucket,

United States Patent O 3,299,548 SCREENING MEANS FOR CLAMSHELL BUCKET Ernest F. Freyer, 5844 Avalon Ave., Chicago, Ill. 60628 Filed Feb. 10, 1964, Ser. No. 343,706 8 Claims. (Cl. 37-483) This invention relates to material handling clamshell buckets or equivalent openable and closable scooping and dumping buckets and, more particularly, to material screening, grading and handling facilities which are such in construction that they can be built into or, alternatively, attached to and properly used in conjunction with a conventional-type clamshell bucket.

A significant aspect of the herein disclosed concept has to do with expeditiously and effectively screening material (various kinds of materials) which has been scooped up, elevated and is being handled in the sectional bucket of a currently usable type clamshell. In keeping with the principles of the invention novel screening means is associated cooperatively with the openable and closable mouth The construction and arrangement is such that when the mouth of the bucket is opened and the lip-like cutting edges are spaced apart a predetermined degree, the material which is to be screened or strained filters through the screen openings while the larger particles are trapped and temporarily maintained in the receptacle part of the bucket. Accordingly, when the mouth of the bucket is fully opened the larger particles can be discharged and accumulated in a pile for proper separation and grading. In keeping with a desirable and a substantially self-functioning phase the screen is hoisted up to assume an out-of-the-way position in a manner to clear the bucket sections for proper return to the digging cycle.

Considered from the point of view that the improvement pertains to material handling, separating and sorting means the invention is such that it permits the addition of screening means to a conventional-type clamshell; that is, a liftable and lowerable construction embodying a pair of opposed companion bucket sections. Each section preferably comprises a pair of end walls suitably shaped and joined by an intervening main wall. This main wall has a curvate or concavo-convex bottom and top portion, these portions cooperating with each other and the end walls in defining the desired receptacle or receiver for the loose or other material which is to be handled. The end walls have common pivot pins hingedly joining the bucket sections in normally closed bucketforming relationship. Rigid links have lower diverging ends hinged to upper corner portions of the respective bucket sections. The upper converging ends of the links are hingedly pinned and thus properly joined to liftable and lowerable hoist means characterized by a cable controlled frame and other component parts. The screening means for the material, that is while it is being handled and separated, is characterized by a screen which is ex-- ternal to the lip-like edges of the mouth of the sectional bucket in a manner to sift, separate and otherwise handle the material in a contemplated manner for piling and grading.

In carrying out a preferred embodiment of the invention the screen proper is of a length greater than the length of the mouth of the bucket and is of a prescribed width so that the trapping and straining area is ample to reliably take care of the screening and separating step,

In addition to the screen, which is framed, the end portions are provided with uprights which coact with the end walls of the respective bucket sections and wherein the upper ends are hinged to the pivot pins which join the end walls of said bucket sections.

It follows that the screening means, considered as a generally at 18 in FIG. 4.

3,299,548 Patented Jan. 24, 1967 unit, resembles a U-shaped cradle. With this construction means of one type or another is employed so that the screening means is not only oriented but coordinated with the existing component parts of the clamshell bucket. By employing an appropriate cable and pulley arrangement the opening and closing movement of the jaw-like bucket sections functions to simultaneously cradle the screen so that it is horizontal and ready for use at the proper stage of functioning and is swung up to a clearing, out-of-the-way position when the scooping and loading step is undertaken.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter de scribed and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a view in end elevation of the bucket part of a socalled material handling clamshell, the latter being of a generally well-known construction and provided, in keeping with the invention, with the pivotally suspended cr-adle-like screening means;

FIGURE 2 is a view based on FIGURE 1 and showing a second step, that is the step wherein the two jawlike bucket sections are partly spread apart to accomplish the screening and separating step;

FIGURE 3 is a View in proper sequence in respect to FIGURES 1 and 2 and which shows the bucket sections spread open and about to dig into and scoop up another load of material (not detailed) and which view serves to show how the cable or equivalent means swings the screening means up to an out-of-the-way position;

FIGURE 4 is a view based on FIGURE 1 and showing the component parts appearing in section and with hends both combination and subcombination aspects the improved clamshell (construed as a material scooping, hoisting and handling device) comprises a sectional bucket characterized by opposed duplicate cooperating jaw-like bucket sections one to the left as at 8 and the other one to the right a at 10. Each section comprises (FIG. 1) a pair of transverse or vertical end walls 12 and an intervening connecting Wall having a generally vertical upper part 14 and a concave-convex lower or bottom part 16. The cooperating lip-like cutting edges are denoted The respective end walls are provided with gradually reduced wing-like members 20 whose upper ends are appropriately interconnected and joined by a pin or shaft 22 (FIG. 5) whereby to thus hinge the sections 8 and 10 together. The upper edge or corner portions 24 are provided with lug-like cars which function to accommodate the lower diverging ends of paired links 26 which are hinged or pivoted: in place as at 2-8. The upper converging ends of the links are pivoted and hingedly connected as at 30 to the end portions 32 of the frame part of the cable controlled hoisting means 34. The hoisting cable is denoted at 36 and has a yoke or the like at its bottom provided with a sheave or pulley38.

The bucket is shown closed in FIG. 1 with the screening means in its normal balanced or suspended position. The screen, if necessary, can be held in a steady position under the openable and closable mouth portion of the bucket by appropriate means (not detailed). While the screening means can be of some other construction and pivoted and suspended in some manner other than that illustrated it is preferably of generally U-shaped form and resembles a simple cradle designated generally by the numeral 40. It comprises suitable frame means 42 (see FIG. 6) and an appropriate screen 44 of suitable gauge or mesh. While the screen is here shown as of rectangular form it is within the purview of the invention that it may be dished or otherwise made concavo-convex to facilitate trapping and sorting the material which is to be screened. As will be evident for example from FIG. 4 the screen is of a width and length comparable'with the digging lip means 18 of the jaw-like bucket sections 8 and 10. The upstanding balancing and cradling arms are spaced parallel and are generally triangular in end elevation and are denoted by the numeral 46. The upper apical ends are disposed outwardly of the end walls 12 of the sections 8 and 10 and are hingedly mounted as at 48 on available end portions 50 (FIG. 5) of the pivot pin or shaft 22. The means for actuating the screening cradle relative to the bucket comprises a cable 52 having a lower end portion 54 suitably connected to a fixed eye or the like 56 on the median portion of the screen (FIG. 6). The upper end portion 58 of the cable is tied or otherwise connected at 60 to the rod or pin 22 as shown in FIG. 5 and a portion of the cable adjacent thereto is trained over the pulley or sheave 38 as illustrated in the various views of the drawing.

There is enough slack in the cable 52 to permit the main shaft of the bucket to move away from the head until the bucket is in the open position (FIG. 2) without moving the screen from its vertical position. The material in the bucket will now screen itself out, and any material that is larger than the screen size will remain in the bucket. As the bucket opens toward the position of FIG. 3, the cable 52 pulls the screen 40 up out of the way of the digging lips and permits the beginning of another cycle.

This screen can be pivoted from other points on the bucket and it also can be raised or lowered by other means and the screen itself can be rounded or in other shapes. There are many ways of attaching, activating or applying this screening principle to clamshell buckets.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. In combination, a material digging, scooping, handling and dumping clamshell bucket embodying a pair of aligned cooperating bucket sections, each section having end walls joined by an intervening main wall having concavo-convex bottom and top portions cooperative with each other and said end walls, cooperating upper end portions of said end walls having axially aligned pivot means hingedly joining said bucket sections in opposed coplanar normally closed bucket-forming relationship, links having lower diverging ends hinged to upper respectively cooperable corner portions of said bucket sections, assembling and hoist means to which upper converging ends of said links are hingedly joined, and screening means for the material while the same is being handled and separated, said means being operatively attached to, liftable and lowerable in conjunction with, constituting a complemental part of said clamshell bucket and embodying an elongated screen external to said bucket and wholly underlying the mouth of the bucket when the mouth is (1) closed and (2) partly open in a manner to sift, separate and otherwise handle the material which is being dumped from said bucket.

2. The structure defined in claim 1, and in combination, means cooperable with said bucket sections and said screening means whereby the screen thereof maintains its screen position until the bucket sections spread apart a prescribed distance, at which stage the screen is caused to automatically assume an out-of-the-way position relative to at least one of said bucket sections soas not to interfere with the digging and loading function of said bucket sections.

3. The structure according to claim 1 and wherein said screen is of a length greater than the length of said bucket and is of a width proportional and capable of serving its sifting and trapping purpose during the stage of operation when the lips of the mouth of the bucket sections start to open and until they have moved apart a predetermined distance beyond cooperating lengthwise marginal edges of the screen, and wherein said screen is provided at end portions thereof with upstanding suspension arms, said arms being pivotally connected at upper ends to the aforementioned pivot means.

4. In combination, a material digging, scooping, handling and dumping clamshell bucket embodying a pair of aligned cooperating bucket sections, each section having end walls joined by an intervening main wall, the latter having bottom and top portions cooperative with each other and said end walls, said end walls having common pivot means hingedly joining said sections in normally closed bucket-forming relationship, links having lower diverging ends hinged to upper corner portions of said bucket sections, assembling and hoist means to which upper converging ends of said links are hingedly joined, and screening means for the material while the same is being handled and separated, said means embodying a screen external to said bucket and underlying the mouth of the bucket in a manner to sift, separate and otherwise handle the material in whatever manner desired, said screen being of a length greater than the length of said bucket and of a width capable of serving its trapping and sifting function during the stage of operation when the lips of the bucket sections are a prescribed minimal distance apart, and said screen being provided at end portions thereof with upstanding suspension arms, the latter pivotally connected with the aforementioned pivot means.

5. Means for screening material of varying grade and character while being handled in the scoop-like companion sections of a clamshell bucket comprising: an elongated screen adapted to assume a trapping and screening position contiguous to but beneath the openable and closable lips of the mouth part of the bucket, means for pivotally and swingably mounting said screen on the bucket, and means operatively connectible to said bucket and screen, respectively, for bodily moving the screen rel-' ative to the bucket so that said screen can assume an outof-the-way position when the bucket-sections are readied to dig and load the receptacle portion of the bucket with material.

6. The structure in claim 5 and-wherein said screen is provided at its ends with integral upstanding bucket attaching and pivoting arms, whereby to thus provide a cradle-like unit.

7. The structure defined in claim 5 and wherein said screen is provided at its ends with spaced parallel upstanding screen attaching and pivoting arms, whereby to thus provide a cradle-like bucket attachment, and, in com-' 'bination, a flexible cable having one end operatively connected to the screen and the other end adapted to be connected with a predetermined part of said bucket.

8. For use on and in conjunction with a conventional type material scooping, handling and dumping bucket of the clamshell type and which embodies a pair of duplicate opposed scoop-like bucket sections having end walls which are joined together at corresponding upper end portions, an attachment which is applicable to and usable in conjunction with the bucket sections and which is connectible thereto without altering existing or stock component parts comprising a horizontally elongated screen of a prescribed mesh depending on the material which is to be screened and graded, said screen being of a length to underlie the openable and closable lips of the mouth portion of said bucket, and being of a width that it underlies said mouth portion when the lips are closed and continues to underlie the same for screening purposes when the lips'are spread apart to a point predetermined and Which permits free gravitation of the material from the receptacle portion of the bucket onto the'screen for spreading and grading, said screen being provided at end portions thereof with means whereby to permit the screen to be hingedly and swingably attached to and hung from said bucket, and means, a cable for example, connected to said screen in a manner to permit the screen to swing to and occupy a screening position or to be displaced and held away from the open mouth portion of the bucket when References Cited by the Examiner UNITED STATES PATENTS 12/1912 Jackson 3757 1/1939 Matthews 3757 X 10 ABRAHAM G. STONE, Primary Examiner.

J. R. OAKS, Assistant Examiner. 

1. IN COMBINATION, A MATERIAL DIGGING, SCOOPING, HANDLING AND DUMPING CLAMSHELL BUCKET EMBODYING A PAIR OF ALIGNED COOPERATING BUCKET SECTIONS, EACH SECTION HAVING END WALLS JOINED BY AN INTERVENING MAIN WALL HAVING CONCAVO-CONVEX BOTTOM AND TOP PORTIONS COOPERATIVE WITH EACH OTHER AND SAID END WALLS, COOPERATING UPPER END PORTIONS OF SAID END WALLS HAVING AXIALLY ALIGNED PIVOT MEANS HINGEDLY JOINING SAID BUCKET SECTIONS IN OPPOSED COPLANAR NORMALLY CLOSED BUCKET-FORMING RELATIONSHIP, LINKS HAVING LOWER DIVERGING ENDS HINGED TO UPPER RESPECTIVELY COOPERABLE CORNER PORTIONS OF SAID BUCKET SECTIONS, ASSEMBLING AND HOIST MEANS TO WHICH UPPER CONVERGING ENDS OF SAID LINKS ARE HINGEDLY JOINED, AND SCREENING MEANS FOR THE MATERIAL WHILE THE SAME IS BEING HANDLED AND SEPARATED, SAID MEANS BEING OPERATIVELY ATTACHED TO, LIFTABLE AND LOWERABLE IN CONJUNCTION WITH, CONSTITUTING A COMPLEMENTAL PART OF SAID CLAMSHELL BUCKET AND EMBODYING AN ELONGATED SCREEN EXTERNAL TO SAID BUCKET AND WHOLLY UNDERLYING THE MOUTH OF THE BUCKET WHEN THE MOUTH IS (1) CLOSED AND (2) PARTLY OPEN IN A MANNER TO SIFT, SEPARATE AND OTHERWISE HANDLE THE MATERIAL WHICH IS BEING DUMPED FROM SAID BUCKET. 